An onlooker tells PEOPLE that "Travis and Kylie were especially cute and lovey-dovey"

The Jenner sisters spent date night with their BOOs.

Kylie Jenner may be keeping an extremely low profile as she prepares to welcome her first child, but she stepped out this weekend for a special double date with her boyfriend Travis Scott, sister Kendall Jenner and Kendall’s beau Blake Griffin.

An onlooker confirms to PEOPLE that Kendall, 21, and Kylie, 20, spent Sunday evening at Universal Studios’ Halloween Horror Nights in Hollywood, accompanied by Scott, 25, and Griffin, 28. The foursome was also joined by Jordyn Woods, 20, and Hailey Baldwin, 20.

“Kylie and Kendall were both extremely loving and cuddly with their boyfriends,” the onlooker says. “Both couples had their arms around each other, and the girls were really sweet with their guys. Travis and Kylie were especially cute and lovey-dovey. Kendall and Blake had a blast going through the mazes together.”

While there were certain rides pregnant Kylie couldn’t go on, she “made sure Travis went ahead and had fun,” says the onlooker, adding that the reality star kept her belly “under wraps in a big hoodie and leggings.”

Kendall and Griffin, who plays for the Los Angeles Clippers, have been hanging out since August. Last week, a source told PEOPLE that the NBA star, who shares two children with Brynn Cameron, a former basketball player at USC, is “super into” Kendall.

Credit: Getty (2)

“She thinks he’s dorky and funny, but also cool and sexy — he has a certain attractive ‘swagger,’ ” the source said. “They are seeing each other more, and Blake is doing everything in his power to make Kendall his girlfriend.”

“She’s always working and traveling and knows a full-blown relationship isn’t necessarily the best idea, but things are heating up,” the source added. “She is for sure enjoying dating him.”

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As for her younger sister, Kylie has remained under the radar since multiple sources confirmed to PEOPLE last month that she’s expecting her first child, a baby girl, with Scott. She’s been dating the rapper since earlier this year after splitting from heron-again, off-again boyfriend of nearly three years, Tyga.

Oklahoma City Thunder v Houston Rockets - Game Five
Travis Scott and Kylie Jenner
| Credit: Bob Levey/Getty

Last week, a source told PEOPLE that Kylie — who hasn’t publicly addressed her pregnancy but seems to be teasing the news on Snapchat — “still wants to keep a low profile” and “prefers to stay home” at the moment.

“Even though this is a very exciting time for her, she wants to be more private for now and is doing her best to stay out of the public eye,” the source said.

“She feels good, but her body is changing,” the source explained. “She doesn’t want to be photographed. At the moment, she wants more privacy. She has family and friends come to her house instead so she has company. She’s very excited about the baby though. She talks about the baby nonstop. She’s already shopping like crazy.”

On Monday, Kylie was noticeably absent from photos of the family shooting their Keeping Up with the Kardashians Christmas special at Kris Jenner’s home with now-retired Olympic medal-winning figure skater Nancy Kerrigan. A source told PEOPLE that she was present during filming, but opted not to ice skate.

“It was a scheduled taping,” the source said. “She kept in the background, but seemed great.”

Keeping Up with the Kardashians airs Sundays (9 p.m. ET) on E!